Physiological impact of sodium azide on Helianthus annus seedlings

Abstract The present study was carried out to demonstrate the effect of sodium azide on Helianthus annuus var.“Giza 53” at the green house of Botany Department, Faculty of Science, Tanta University, Egypt. Seeds were soaked in different concentrations of sodium azide (0.5, 1.0 and 2.0 mM) for different time intervals (30, 60, 90, 120 and 150 minutes). Control was maintained by soaking the seeds in distilled water only. The increased concentrations of sodium azide and time of soaking had a negative effect on the percentage of germination, shoot height, chla, chlb, lipid peroxidation and catalase activity. Increasing the concentrations and time of soaking of sodium azide stimulated the antioxidant defense of Helianthus annuus by increasing carotenoids, peroxidase activity and protein content. Pattern of protein was changed with increasing concentration and time of soaking.